1. Technical Field
The present invention relates to a liquid ejecting apparatus and a maintenance method of the liquid ejecting apparatus.
2. Related Art
An ink jet printer (hereinafter referred to as a “printer”) capable of ejecting ink (liquid) droplets onto a printing medium from ejection orifices (nozzles) of a printing head (liquid ejection head) is known as a liquid ejecting apparatus.
Such a printer includes a tank for containing ink therein, and supplies the ink inside the tank to the printing head and ejects the ink from the printing head. The ink is generally made of a dispersion liquid containing solid content, such as pigment or the like, and a dispersion medium such as solvent.
In a case where the printer uses the ink, in particular, if the printer is powered-off and is maintained in a disused state, the solid content contained in the ink contained in the tank is separated and settled (sunken), so that the concentration of the solid content in the ink becomes uneven. If the solid content is settled and thus the concentration of the solid content becomes uneven, when the ink is ejected by again turning the power on after the power is turned off when the printing is carried out, the solid content settled in the tank is supplied to an ink jet head side as it is, such that the nozzles of the printing head are clogged or unevenness defects are produced in the printing quality.
In order to prevent such a problem, there is known a printing apparatus (printer) including two supply passages which are provided to communicate with the tank for storing (containing) the ink with the printing head, to circulate the ink between the printing head and the tank (for example, refer to JP-A-2007-331281).
However, there is a concern that the circulation of the ink may cause inflow of gas from an ejection head in the above-described configuration.